/*
    Copyright (c) 2016 Arduino LLC.  All right reserved.

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    See the GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

#ifndef _PDM_DOUBLE_BUFFER_H_INCLUDED
#define _PDM_DOUBLE_BUFFER_H_INCLUDED

#include <stddef.h>
#include <stdint.h>

#define DEFAULT_PDM_BUFFER_SIZE 512

class PDMDoubleBuffer {
public:
    PDMDoubleBuffer();
    virtual ~PDMDoubleBuffer();

    void setSize(int size);
    size_t getSize();

    void reset();

    size_t availableForWrite();
    size_t write(const void *buffer, size_t size);
    size_t read(void *buffer, size_t size);
    size_t peek(void *buffer, size_t size);
    void* data();
    size_t available();
    void swap(int length = 0);

private:
    uint8_t* _buffer[2] __attribute__((aligned(16)));
    int _size;
    volatile int _length[2];
    volatile int _readOffset[2];
    volatile int _index;
};

#endif
